A seat belt in a vehicle may be equipped with “load limiting” features. During a collision, a retractor of the seat belt may lock webbing of the seat belt from further extension from the retractor, but load limiting features permit some additional limited extension of the webbing when the force exerted on the webbing exceeds a load-limiting threshold.
Different load-limiting thresholds may be applicable to different types of occupant. A relatively low load-limiting mode, i.e., a lower threshold force before the webbing extends, may be applicable to adults. On the other hand, a relatively high-load limiting mode may be applicable to an infant or young child in a child car seat installed to the vehicle seat, in which case the child car seat is more firmly positioned on the vehicle seat.
Another feature of a seat belt that may be helpful to child car seats is an automatic locking retractor. When an automatic locking retractor is engaged, the webbing of the seat belt is permitted to retract but not extend. The webbing of the seat belt then may keep the child car seat more firmly positioned on the vehicle seat.